Apparatus for cement manufacture and process for operating the same



Aug. 24 1926.

- E. G. WEEKS APPARATUS FOR CEMENT MANUFACTURE AND PROCESS FOR OPERATING THE SAME Filed Feb. '7, 1922 2 Sheets-Sheet 1 Aug. 24 1926.

E. .G. WEEKS APPARATUS FOR CEMENT MANUFACTURE AND PROCESS FOR OPERATING THE SAME Filed Feb. '7, 1922 2 Sheets-Sheet 2 I Patented Aug. 24, 1926.

'uNir n 's rA 'r-as 1,596,956 PATENT OFFICE.

EDMUND GEORGE wmixs, or uonrnumnnnmim, ENG-LAND, nssrenoa 'ro THE rum MEBZ ain mnm, or wnsrmmsrim, LQNDON, ENGLAND, A. nnrrrsn mam.

nrrnnn'rus iron muracru'na AND rnocnss ron ormrme THE same. i

' Application march-n ry 1922, swarm.

This-invention consists in improvements in .or relating to cement manufacture and has for its object to provide a process for operating ai'cement kiln and a plant to be I used in connection therewith whereby decreased cost of manufacture isefi'ectedin comparison {with processes and plant hitherto employed;

Accordingto' the present invention a process forfopeiatingjacement kiln consists in V firing the kiln with coke residue from a fuel carbonization plant," preferably alow-temaccording to the present invention will now -be described by way of example with refer:- ence to the accompanying drawings which are to be taken as purely diagrammatic illusperatuie' icarbo ni'zation plant; with or withouttheaddition of other fuel (such for example a sf powderedraw coal or residual oils obtained semi-11s carbonization process or both); and utilizing the heat of the ez zhaust gases from 'thejki' for" eating said carans-amphe additionahhea't isfrequiredifor' the 'it is suppliedgbybu Y,

the'afbrtsaid carb nization- 1ant 1 Conveiii'entlygl' thefcokeresidue, with'or ,witheutraw powderd fuel, 'suchas coal, is

admirer with residual. oils produced b'ythe' 'carbonization "of, the" fuel to 1 form a ;colloid fuel whichisfjfed tothe as such;

" r fThe term eclloid fuel is "intendedtoini cludefa substantially homogeneous mass in I "which [he solid -p rticles areheld' in su'spenv i a The partly finished cement or clinker is discharged from the lower end of the kiln is'ion inthe' oils'l' QIILT9Q residqerromthe carbonizfatlon plant may a5 r d tcfthe kiln are heated condition.- I

1' f1 Appa tus th invenfidli m y "compris e broadly" in'fcombination a low-temfuel-carbomz ationiplant; a'cem'ent s m-plant:comp t m- Jase hatefqran Of-"them, meansto convey hot the to the said steam;

plantgafllf eansto pass steanitherefrom l" distillation? retort operating bntih ibu li wrcimeni il nnic ating between'the' re-- A to transfer-coke residue tort in ajheat'ed or partially 'g' the obtained from afurther fuel economy coke or snp erheating apparatus or feedand a preheater 14 for the "boniliatiomplant-to supply" 7 --fuel from a pit 16 (into which it is discharged from trucks) 'to the; preheater cha'm her." The general features of this part of the apparatus are preferably also includes the combina- I 534,731, aid in Great Britain Irma 11, 192 1.

sing; among other dis advantages, is obviated.

- An advantage of the present invention is virtually reduced on account of the value of. I the oils and other by-products so obtained.

- Two preferred arrangements of apparatus trations in whicht Figure 1 shows in outline one general v 9 I I arrangement of combinedcoal-carbonization According toa feature of the in'vention', if Y i Figure 2 shows a modified arrangement in which the steam generating plant derives the major portion. of its heat .fromthe retort ases.

. 'Like "reference nlimerals indicate like plant and cement kiln;

l 1, there is provided a cement kiln 10 of 'the inclined rotary cylinder type to which slurry the usual-manner through a feed-conduit 11.

into 'a cooler 12 through which the air suprportin'g combustionis' conveniently passed,

the 1 air becoming preheated travelling through the cooler.

-In'proxim1tyto the discharge end of the cement kiln .is a low-temperature fuel-car- 'bonization plant, conveniently operating with a distilling temperature not exceeding a retort 13 el supplied 550 to 600 C. and comprisin thereto with an-elevator 15 for raising; the

those described, for example 1n. the specifi- 17- into which coke from the retort. is deisiintroduced at the higher or upper end in livered and is pulverized in a hot or partially cooled condition. The pulverized coke is passed, by means of a fan 18, through a delivery conduit 49 and thence into the lower end of the cement kiln. With the fuel, if desired, there may be fed into the kiln powdered raw coal and/or residual oils ob-. tained from the carbonization process.

For generating steam required for heating the retort, and thereby distilling the fuel therein, a boiler 19 working at low pressure is installed at or near the base of the chimney 20 (provided with a damper 51) through which the waste hot flue-gases escape from the cement kiln.

The distilled gases leave the upper end of the retort by way of a pipe 50 and are passed first through a condenser 21 within-which there is a coil 22 for the passage of feedwater from a pump 23 to the boiler 19. From the condenser the uncondensed gases pass to an additional gas-cooler 24 through which cooling water clrculates in a coil 25 disposed therein. The cooled gas is led to a by-product recovery plant 26 where motorspirit and other products are recovered from the gas, the stripped or treated gas passing therefrom to a burner 27 employed for heating a superheater 28 for the steam as it leaves the boiler. The waste gases leave the superheater 28 through the upper end of a casing 29, pass up beneath the boilerq lthus by-passed.

and eventually escape through the main chimney 20, imparting their heat to the boiler in so doing. The condensed oils extracted from the stripped or treated gas in the condenser 21 and plant 26 are collected in sumps 30 and 31 respectively.

Steam from the superheater passes through a pipe 32 leading to the lower end of the retort. The major portion of this pipe is jacketed by a second pipe 33 through which is drawn by means of a fan 52 a portion of the exhaust gases passin up the main chimney 20. The pipe 33 delivers into a jacket 34 surrounding the retort 13 and from thence the exhaust gases are led to the preheater 14 from which theyfinally escape through the chimney 35. The exhaust gases thus serve, not only to prevent heat-radiation from the steam-pipe 32, and from the retort, but also to heat the preheater.

In the event of the heat in the waste gases from the kiln and from the superheater be ing in excess of the requirements for the boiler, the ,whole or part of the waste gases may be by-passed round the boiler through a by-pass conduit 34 wherein a damper 35 If, on the other hand, the heat in the waste gases is insufiicient for the requirements of' the boiler, additional heat may be provided therefor, in the form ofgas, powdered fuel or oil burned in auxiliary burners such as the amount of gases above, and for this 36, disposed beneath the boiler. The materials thus burned may be products from the carbonization plant.

Theqsecond form of apparatus diagrammatically illustrated in Figure 2 is applied to cases where the heat in the waste gases from the kiln is known to be insuflicient for generating the steam required for the retort. In this case the cement kiln and coal-carbonization plant, (with the exception of the byproduct recovery portion thereof) and the means for feeding the kiln and the corbonization plant are the same as in the arrangement shown in Figure 1. Part of the steam for the retort is generated in the boiler 19 which in this case is situated in the same casing 29 as a superheater 28 below it, the upper end of the casing being in communication with'the main chimney or exhaust stack 20'from the kiln. Feed-water for the boiler'19 is supplied from any convenient source and is circulated by means of the pump 23 through an economizer 37 disposed in the chimney and thence to the boiler, from which steam is thereafter passed into the superheater 28 and .through the jacketed steam-conduit 32, as before, to the retort. The retort gases enter the pipe 50 and are passed in succession through three heat-interchangers 39, 40 and 41 arranged in series, the first unit 39 constituting ,a superheater, the second an evaporator, and the third a feed-water heater. QWater for cooling the retort gases and supplying the evaporator is circulated by a pump 38 on thecontra-flow principle, entering first the unit 41 and then passing to the unit 40. Steam generated in the latter is slightly superheated in the unit 39 and from thence passes by way of a pipe 42 and pressure:

booster 43 to the superheater 28, where it joins steam from the boiler 19, and passes in company therewith to the retort. The distillate from the retort which is condensed in the heat-interchangers is collected in a sump-30. Gas from the unit 41 is passed through a cooler 24 and by-product plant 26Xas before, the stripped or treated gas being burned at 27 to sup ly heat to the main superheater 28. If ad itional heat is required for the boiler '19 to augment the heat in the gases leaving the superheater, a burner 44 may be provided in which fuel of any preferred form is consumed.

It will be understood that the two arrangements of apparatus described above are given by way of illustration only and'are capable of many modifications without departing from the spirit of the invention. For example, the superheater may be fired by any means other/ than that described fpurposeproducer-gas or pulverized ,fuel, or example,-may be employed. It is also within the invention to supply, as fuel for the kiln, a colloidfuel composed of powdered coke residue and residual oils obtained from the coal-car'- bonization plant. Moreover, gas from the latter can also be burned within the cement kiln and other raw solid fuel may be added if desired, separate burners being provided to feed the different fuels to thecombustion zone of the kiln.

What I claim as my invention anddesire to secure by Letters Patent is 1. A process of operating a cement kiln in conjunction with a low-temperature fuelcarbonization plant the still of which is heated by steam, which consists in firing the kiln with coke residue from the fuel-carbonization plant, and utilizing the heat of the exhaust gases from the kiln for generating the steam to be supplied to the still of the fuel carbonization plant, substantially as described.

2. The combination of a steam-heated low-temperature fuel-carbonization still or retort, a cement kiln, a steam-generating plant, means to convey exhaust gases from the cement kiln to the steam-generating plant for heating the same, means to pass steam thus generated to the'still or retort to supply heat thereto, and means for feeding into the kiln pulverized coke'residue from. thestill or retort for firing the kiln therewith, substantially as described.

' retort, a cement kiln, a steam-generating- 43. The combination of a steam-heated low-temperature fuel-carbonization still or retort, a cement kiln, a steam-generating plant, means to convey exhaust gases from the cement kiln to the steam plant, means to pass steam therefrom to the still or re 'tort to supply heat thereto, means for feed; ing into the kilnpulverized coke residue from the still or retort for firing the kiln therewith, and means associated with the steam-plant for burning gas obtained from the still or retort thereby to assist in the heating of said steam-plant, substantially as described; 7.

4. The combination a steam-heated low-temperature fuel-carbonization still or plant, means to convey exhaust gases from the cement kiln to the steam-plant for heating the same, means to pass steamtherefrom to the still or retort to supply heat thereto,

means for feeding into the kiln pulverized coke residue from the still or retort for firing the kiln therewith, means associated with the steam-plant for burning gas obtained from the still or retort to assist in the heat of said steam-plant, and apparatus for treating said gas and recovering the byproducts obtained from the carbonization of the fuel in the still or retort before gas is supplied to the steam-plant substantially as described.

5. The combination of a steam-heated low-temperature fuel-carbonization still or retort, a cement kiln, a steam-generating plant, means to convey exhaust gases from the cement kiln to the steam-plant for heating the same, a heater, an evaporator and superheater acting in the dual capacity of a condenser for the gases from the still or retort and of a steam-generating plant to provide additional steam for heating the still or retort, and means for injecting pulverized coke residue from the still or retort into the cement kiln.

6. The combination of a steam-heated low-temperature fuel-carbonization still or retort operated substantially continuously, a

cement kiln, a steam-plant comprising steam-generating and superheating apparatus, means to transfer pulverized coke residue in a heated condition from the still or retort to the kiln, means to convey exhaust gases from the kiln to said steam-plant for heating the same, and means to pass steam from the latter to the still or retort to supply heat thereto.

7. The combination of a steam-heated 'low-temperature fuel-carbonization retort, a

EDMUND GEORGE WEEKS. 

